>Does the universe have magnetic poles?
Almost certainly not. For one thing, because the magnetic field has no way to exist in space outside the Universe itself, and because the Universe itself is effectively a giant four-dimensional sphere, having a magnetic field across the entire Universe would probably require the existence of magnetic monopoles (objects that have only one magnetic pole). Although most prominent theories do actually allow for the existence of magnetic monopoles, no such particles have ever actually been detected with scientific instruments, and it seems that if they do exist, they would be extremely unstable and would decay into other particles in a tiny fraction of a second. So unless either one, our theories are wrong, or two, some extremely large intelligent civilization is deliberately maintaining the magnetic field using artificially produced monopoles, it seems highly unlikely that there is a Universe-spanning magnetic field.
That said, there is nothing stopping magnetic fields from existing on smaller, but nevertheless extremely vast, scales. Theoretically, you could for example turn an entire galaxy or galaxy cluster into a magnet if you wanted to. In fact, scientists believe that our galaxy does have its own magnetic field, although this field is extremely weak, over 100000 times weaker than the Earth's magnetic field (about 10^-10 teslas as compared to about 10^-4 or 10^-5 teslas for the Earth). Naturally existing fields on a larger scale would probably be far weaker still, and like I say, because of the structure of space, without magnetic monopoles the collective magnetic fields should necessarily cancel each other out on the scale of the entire Universe.
>Then again, is the solar system plane on the plane of the milky way galaxy?
I don't think it is. Although star systems may tend to match the plane of their galaxy on average, most of them are oriented more or less randomly. In many cases, objects may even orbit a star outside of the star system's own plane, for example all eight plants in our Solar System lie approximately in the same plane but Pluto's orbit is tilted I think over 20 degrees off that plane and some comets have orbits that are even more tilted.